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arXiv · 1003.5207

Superconductivity in strongly repulsive fermions: the role of kinetic-energy frustration

L. Isaev·G. Ortiz·C. D. Batista
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Abstract

We discuss a physical mechanism of a non-BCS nature which can stabilize a superconducting state in a {\it strongly repulsive} electronic system. By considering the two-dimensional Hubbard model with spatially modulated electron hoppings, we demonstrate how kinetic-energy frustration can lead to robust d-wave superconductivity at {\it arbitrarily} large on-site repulsion. This phenomenon should be observable in experiments using fermionic atoms, e.g. ${}^{40}K$, in specially prepared optical lattices.

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L. Isaev, G. Ortiz, C. D. Batista. 2010-03-26. Superconductivity in strongly repulsive fermions: the role of kinetic-energy frustration. https://doi.org/10.1103/physrevlett.105.187002

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